Grinding machine



Dec. 8, 1964 w. PECHY 3,159,948

GRINDING MACHINE Filed March 8, 1963 5 Sheets-Sheet l AMOUNT or l "25 GRlNome 5 64 INVENTOR. W/L L//IM PECHY.

L l l Wm HWF/VEZ Dec. 8, 1964 w. PEcHY GRINDING MACHINE 3 Shee'os--Sheefl 2 Filed March 8, 1965 Ew mv ov mm mv vm si Om .E E S ov Nm Dec- 8, 1954 w. PEcHY 3,159,948

GRINDING MACHINE Filed March 8, 1963 3 Sheets-Sheet 5 FIG. 7. 45 l Flea.

PUSH

United States Patent C) 3,159,948 GREJDNG MACEEJE William Peehy, Wali Township, Monmouth County, NJ.,

assigner to Westinghouse Electric Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Filed Mar. 8, 1963, Ser.. No. 263,872 6 Ciaims. (Cl. Sil-3d) This invention relates to grinding machines, and more particularly to such machines for a grinding operation on terminals of uorescent lamps. y

In the manufacture of iiuorescent lamps, the terminal or terminals project at the ends of the lamps, and for simplicity, lamps chosen for the present disclosure have a single such terminal projecting axially from at least one end of the lamp, coaxially thereof. The invention, however, is applicable to lamps having more than a single terminal at one or both ends of the lamps. Y

Among the principal objects of the invention, is the general purpose of provision of a machine which will automatically and with successive rapidity, prepare a terminal to be ready for final-soldering operation thereon.

In a broad aspect of the invention, the basic object thereof is to prepare a terminal in a manner such that when soldering is thereafter effected for the lead-in wires thereto, the ends of the lead-in wires will be so short as not to possibly protrude outwardly through the solder tip, and yet the lead-in wires are long enough to be securely soldered in the terminal.

A more specific object of the invention is to remove that portion of the lead-in wires previously left projecting from the terminal during operation of assembly of the cap, of which the terminal is a part, upon the tubular envelope of the lamp.

In addition to the foregoing operational objective, the invention proposes grinding both the terminal and the lead-in Wires simultaneously to produce a somewhat flattened end on the terminal beyond which the Wires then will not project.

The invention contemplates such precision in the grinding off of the successive terminals that subsequent solderwill return the terminal exactly to the desired length and dome-like condition with use of the same amount of solder each time.

An important accomplished purpose, therefore, is to provide a machine which will automatically place the lamp terminal at a position with such precision that the terminal is ground at its end not only to the necessary amount, but Without excessive removal of material from the terminal end.

As a corollary objective to the foregoing one, the invention proposes automatically accommodating the machine to perform its function under conditions of progressive wear or erosion of the grinding'element.

Before entering upon detailed description, it is pointed out that the invention displays structural novelty by which the lamp is located longitudinally and is gripped when so located and is held immovable during grinding of the terminal.

And nally, let it be said that a Structural attribute of the invention resides in the provision of means gauging the ground condition of a lamp terminal while the lamp is still gripped and immobile, to reset the grinding element, if necessary, for more accurate grinding of the next successive lamp terminal awaiting grinding.

Other objects, advantages, beneficial results and structural features will appear to persons skilled in the art to which the invention appertains as the description proceeds, both by direct mention thereof and by implication from the context.

Referring to the accompanying drawings, in which like nice numerals of 'reference indicate similar parts throughout the several views;

FIGURE 1 is ari-enlarged fragmentary sectional side view of a cap and center contact or terminal of a slim line uorescent lamp illustrative of the critical small amount of grinding or removal of terminal metal to be performed by the machine of this invention;

FIGURE 2 is a side elevation of that portion of a lamp machine at which the present invention is incorporated; FIGURE 3 is an enlarged, cross-section taken on line III--I1I of FIG. 2;

FIGURE 4 is an enlarged, detail cross-section on line IV-IV of FIG. 3, showing the automatic means for adjusting the grinding element carriage toward the work;

FIGURE 5 is an elevational view, partly in section, locking vfrom right to left at the machine as shown in FIG. 2;

FIGURE 6 is a sectional view of a gauging device taken longitudinally thereof, and showing diagrammatically therewith a four-way air valve controlled to supply air pressure to the grinding element air cylinder carriage adjustment; and

FIGURES 7, 8, 9 and l0 are sectional plans of the crucial portion of the machine of the present invention, showing successive steps of operation and relation of the lamps to the machine at each operational step.

It is common practice in manufacture of iluorescent lamps to extend a lead-in wire or wires from a lamp electrode located within the bulb or tubular` envelope, voutwardly through a hollow terminal integrally formed on and protruding from a cylindrical cap cemented on the end ofthe envelope. The outer end of the terminal is substantially semi-spherical or dome shaped with a small hole at the crest thereof through which said wire or wires protrude. The wire is of small gauge and can be readily bent laterally, but has to have the protruding portion thereof notronly entirely removed, but removed far enough back so as not to protrude through a subsequently applied solder tip at the end of the terminal, and it is this operation of wire and metal removal at the terminal end that is performed by the present machine. Such removal of protruding wires and of terminal metal is accomplished by a grinding element shown herein as awheel of abrasive character. Itis emphasized at the outset that the grinding has to be adequate but not excessive. The relation of the terminal end and the grinding element surface is consequently critical, and location of the terminal end not only has to accommodate the thickness yof the bent-over wires, but also has to automatically recognize wear or erosion of the grinding element in the successive presentation of the lamp terminals to be ground. As will appear more in detail in the following description, the lamps are introduced into the machine in spaced parallelism to each other, and arev advanced with a step-by-step motion,

referred to in the trade as being indexed. Between the` periods of forward transition of the lamps, there is a` period of rest, and it is at'the period of rest for each lamp that the automatic adjustmentv of the grinding wheel is effected followed by grinding of the next succeeding lamp; l

In the speciiic embodiment of the invention illustrated' in the drawings, lamps 15 of slim tubular fluorescent typey with caps 16 cemented on the'ends thereof and havingl centrally locatedrcontact elements or terminals 17 projecting coaXially outwardly from the lamp envelope and cap, comprise the work pieces foibe operated upon by the machine about to be described. In FIGURES 7-`. 10, a sequence of several lamps are specifically identified in,

the order of passage through the machine by reference characters A, B, C and D. The machine provides an' appropriate frame 2t) across which is mounted a sprocket shaft 21 having two parallel sprockets 22 thereon spaced apart a distance less than the length of the lamps so that chains 23 on said sprockets and extending to like sprockets at the other end of the machine may be utilized conveniently for feeding the lamps successively in parallelism to each other in a forward direction transverse Vto' the axes of the lamps The chains 23 are provided with upstanding dividers 24 between which the lamps are placed for effecting the forward parallel movement thereof. Placement Wheels 25 are located adjacent to said sprockets and fixed on said shaft to rotate inV unison with the sprockets. Said wheels have peripherally located sockets 26r for reception of lamps 15 fed thereto down a chute 27 said sockets being arranged to coordinate with the successive spaces between dividers 24 so that a lamp-will be fed into each space between thek advancing dividers. This general construction of chain drive and lamp feeding thereto is known in the prior art so that more detailed description is not deemed necessary. The sprockets and chains are advanced by a step-by-step motion, known-as indexing, from a suitable or well known drive (not shown) transmitted to said shaft 21 in any desirable manner, as by a chain 28 and toothed wheel 29. The lamps accordingly are advanced a step at a time and have a period of rest or non-advancement intervening between each step :of advancement.

Occupying space opposite ends of several of the lamps,

the lamp is held both from longitudinal movement and fromtwisting. At this stage of operation, the lamp is both properly located and rmly gripped. At this stage and as shown in FIG. S, the carriage has moved a distance of d/Z, bringing the grinding element 36 into operative engagement with the lamp terminal 17 of the clamped lamp (B in the presently described instance), the lamp of course remaining xed and the period of rest for the chain drive continuing to be effective. l

The grinding element 35 comprises a-rotating grinding wheel of abrasive material which of course issubject to wear or erosion in use at its periphery which is directed toward the end of the terminal, and bent over Wires, which has engagement with a cam 33. The working stroke of the carriage is ina direction opposite to the forward direction of movement of the lamps, and takes place in its entirety while the lamps are in their state of rest. The full stroke of the carriage .is a distance d (see FG. 9) equal to the distance between successive lamps, or in other words is equal to the distance traversed by the chain drive for each step of movementl thereof. The reverse movement of the carriage back to its initial position occurs in the same directiony as and substantially simultaneously with the forward step of llamp movement. VThe cam 33 is on a shaft 34 the rate of rotation of which is coordinated with the lamp chain advancement'.`

On the carriage are mounted three instrumentalities,

Y namely, a stop 35, a grinding element 36 and a gauge 37 which make successive engagement with a lamp terminal during a period of rest of that lamp opposite the car- Y riage. Y

. Looking at FIG. 7, the lamp feed is at a period of rest and the carriage is at what is-herein termed its initial position, andat such position, stop on the carriage is opposite the end of lamp B. At the opposite side of the machine, engaging theopposite terminal of lamp B, is a pusher 38 (see FIG. 5) appropriately operated in coordination with the operation of the lamp feeding mechanism, to push the lamp toward said stop 35 and engage the lamp terminal 17 thereat endwise against said stop. The lamp is then clamped in that position, the clamping remainingelective until the carriage has completed its working stroke. Preferably clamping of the lamp is effected near both ends of the same, as shown in FIG. V5. -TheY particular clamping means chosen for illustration herein comprises a skid 39 fixed.v with respect to frame 2t? and which is slightly higher than the resting surface for the lamp on the feed chain 234 so 'as to eliminate influence of wobblerof the chain. A clamping jaw 4t) vertically movable on` a track 41 is operated under control of a lever 42 with appropriate spring bias (not shown) included in the drive for said lever from the same shaft 34 from which the carriage 39 is driven. The skid and clamping mechanism justdescribed are in essence duplicated at the opposite end of the lamp, and arranged to function simultaneously so it grinds off. The grinding element 36 is journaled in a supporting stock 43 mounted on a table 44 (see FIG. 3), said table being movable in a direction toward the lamp end. On the table 44 is also secureda motor 45 having' driving connection to the grinding element for constantly rotating the same. The relationshipof the grinding element to the terminal end is critical, and has to be maintained at precisely the proper place both to Vgrind olf the wires and to grind off a plateau at the crest of the dome end of the terminal, but without grinding through the entire .thickness of the metal constituting said dome. While the Wear or erosion of the grinding element is ininitesimal from one grinding of a terminal to the next, it becomes cumulative in effect, so it-isdesirable to provide for constant adjustment as each grinding is completed, and for accomplishment of this objective, the aforementioned gauge 37 is provided for contact with the previously ground terminal.

Gauge'37 comprises a plunger 46 which has a direction longitudinally toward the ends of the lamps and adapted to be brought Vinto axial alignment with the lamp immedi=I ately after that lamp terminal has been ground. The plunger 46 has a button head 47 of convex configurationso as to easily ride onto the plateau formed at the end of the terminal by the grinding operation. The plunger is slidably mounted in housing 4S of electrically insulative material, and as best shown in FIG. 6, is engaged by a brush or' other contact means 49 provided in that housA ing. At the rear end of the plunger is an adjustable contact means S6 carried byV a bracket 51 supported by and secured to the insulative housing 48. External electrical outlet connections 52,; 53 are provided for said re spective contact means 49, respectively. The plunger Y is actuated by a spring 54 in a direction tending to move button head 47 toward the lamp. An annulus 55 within the housing 4S and made fast on said plunger transmits the spring pressure to said plunger and also acts as a stop by engagement with the housing to limit the extent of outward movement of said plunger and thereby posi-A a'terminal, when the plunger button 47 comesto juxtaposition with that terminal, the plunger will be depressed and the electrical circuit completed. On the other hand, if adequate depth of plateau has been accomplished by the grinding element, the plunger then does not make suchy engagement with the rear contact member and the electrical circuit remains open.

Closing` ofthe electrical circuit above mentioned is for Y purposes of advancing the grinding element the desired amount of infinitesimal character necessary to obtain adequate grinding of depth of plateau on the terminal of the next lamp in succession. The plunger and its associated electrical circuit is utilized as a trip mechanism to a wellknown electricallyoperated air pressure supply valve 56. When the solenoid 57 of said valve is electrically ener- 3 gize'd, the valve ports pen passage of air pressure from source of compressed air indicated in FIG. 6 by pipe 58, to a feed pipe 59 leading to the underside of a piston in a cylinder 61 shown in FIGS. 2, 3 ,and 5. The piston has a piston rod 62 projecting therefrom through the sealed top of the cylinder and a return pipe 63 goes back to said valve. This return pipe receives air pressure when the valve has a setting under condition of no electrical current actuating the solenoid. The piston rod 62 consequently Will be positively actuated by the air pressure in an upward direction when the electrical circuit is closed and in a downward direction when the electrical circuit is open. Movement of the piston rod directly operates a lever 64 thereover by an intervening yoke 65 connected to said lever and mounted on said piston rod. An adjustable stop 66 is provided beneath said lever for limiting downward movement of said lever.

The above-mentioned lever 64 is provided for the purpose of rotating a screw 67 (see FIG. 3), the axis of which is parallel to the axes of the lamps. The pivoting of said lever is upon the same axis with said screw. Coaxial with the screw and lever and located between the same, is a ratchet wheel 68 having fixed attachment to the screw as by means of an intervening coupling 69. The lever 64 has a spring-loaded pawl 70 pivoted thereon and engaging the ratchet wheel in a position and manner to actuate the ratchet wheel and its connected screw 67 in a clockwise direction when the lever is swung upwardly. An opposite spring-loaded pawl 71 engages the ratchet wheel and functions as a deterrent to backward or anti-clockwise rotation of the ratchet wheel and screw. An unthreaded stern portion of the screw extends rotatably through a lug 72 constituting a fixed part of the carriage, and is suitably retained against longitudinal movement therein. The threaded portion of said screw 67 passes through and has threaded engagement with a second lug 73 which in this instance is integral with and depends from table 44. As the table is movable in a direction toward the lamps and the screw extends in the same direction, it will now be apparent that rotation of the screw will advance the table toward the lamps, and since the grinding element is carried by said table, it is thereby advanced in its grinding position. Preferably the threads of the advancing screw 67 have iine pitch so that a small rotative movement of the screw will result in a very slight advancement of the table. Also, the advancing pawl 70 produces a very short stroke with each swing of the lever on which it is mounted, preferably only a single-tooth movement of the rotative arc. Consequently each advancement of the grinding element towards the work willA be infinitesimal and only occurs when an insufficiently ground terminal causes electrical contact to be made by gauge 37.

It will be appreciated that when the grinding element is performing its function in engagement with a lamp terminal, it tends to push the table rearwardly. It is desirable to keep the table pushed rearwardly, taking up any slack that may exist in the threads or mounting of the screw 67 or elsewhere. For this purpose, FIG. 3 indicates presence of a compression spring 74 bearing against a lug 75 of the table in a direction contra to advancement of the table by screw 67, with the other end of said spring seated in an appropriate socket prepared for it in the carriage. The compressive force applied by use of this spring 74 may be adjusted by use of a screw plug against which the spring is seated in said socket.

Having now an understanding of the mechanisms involved, a brief review of operation by reference to FIGS. 7-10 is in order. It will be remembered that the indexing operation of the lamp-carrying portion of the machine provides periods during which the lamps are at rest. FIG- URES 7, 8 and 9, represent the lamps during the same period of rest, and during that period it is the carriage 30, carrying stop 35, grinding element 36 and gauge 37 that does the moving. Lamp B is pushed against stop at d initial position of the carriage, and having been thus pushed, the lamp is immediately clamped against the underlying skids 39 by jaws 40 and remains clamped as shown in FIGS. 8 and 9 while the carriage moves and the grinding element 36 and gauge 37 perform their functions. Then it is that the jaws 40 release the particular lamp B as has occurred in FIG. l0, whereupon the machine indexes to bring in a fresh lamp C and likewise the carriage 30 returns to initial position so that the terminal of lamp C may be pressed against sto-p 35 and the cycle repeated. Next follows lamp D, and so on repetitiously for all lamps fed successively to the machine. Mention may be made, that the gauge 37 makes its test of the depth of grinding on the lamp terminal While the lamp is still clamped, and if the gauge determines that a deeper grind is necessary, the grinding wheel is moved innitesimally forward and ready in its new position to grind the next terminal that much deeper. The electrical contact and completed circuit due to an insufficient grinding operates the air valve 56 to supply air pressure to the bottom of cylinder 61 and thereby swing lever 64 upwardly yand rotate the ratchet wheel 68 and the table-shifting screw 67. When no electrical contact is being made and the electrical circuit is open, the air valve directs the air pressure to the top of said cylinder 61 so that said lever 64 is located at the lower position of its amplitude of swing ready to be actuated upwardly again when the gauge 37 determines further advancement of the table is needed.

The rate of erosion of the grinding element is ordinarily very slow and shifting of the table 44 to advance the grinding element is not required for each terminal, but occurs only occasionally. A soldering machine for effecting soldering of the lead-in wires to the ground terminals is disclosed in copending application, Serial No. 263,871, iled concurrently herewith by the present inventor, titled Soldering Machine and Product, and owned by the present assignee.

It will be recognized that the objects of the invention have been achieved by providing an improved grinding machine which automatically and rapidly prepares a lamp terminal for a soldering operation. The machine automatically adjusts for any wear or erosion of the grinding element.

While a best embodiment has been illustrated and described in detail, it is to be particularlypunderstood that the invention is not limited thereto or thereby.

I claim:

1. A grinding machine comprising, means for successively advancing lamps inaxial parallelism with lamp terminals projecting from the ends of said lamps, a grinding` element engageable with the end of a terminal of a first lamp for forming a plateau on the end of said terminal, and means gauging the depth of grind of said formed plateau for determining depth of grind of plateau for the next successive lamp terminal. y

2. A grinding machine comprising, means for successively advancing lamps in axial parallelism, said lamps having terminals projecting from the ends thereof, a grinding element engageable with the end of a first terminal for forming a plateau on the said end, said grinding element having a mounting enabling said element to be shifted in a direction toward said terminal end, a gauge for determining sufficiency of depth of grind of said plateau, and means controlled by said gauge and operable when said gauge determines insufficiency of grind of said first terminal'to shift the grinding element to grind the y plateau of the next successive terminal deeper.

3. A grinding machine comprising, means for successively advancing lamps in axial parallelism, said lamps having terminals projecting from the ends thereof, a grinding element engageable with the end of a irst terminal for forming a plateau on the said end, said grinding element having a mounting enabling said element to be shifted in a direction toward said terminal end, a gauge for determining insufliciency of depth of grind of said plateau, an electric circuit, said gauge having means for closing said electric circuit when said gauge determines insuiciency of grind of said first terminal, and means responding to closing of said electric circuit to shift said grinding element to grind the plateau of the next successive terminal deeper. Y

4. A grinding machine comprising, means for successively advancing lamps in axial parallelism, lsaid lamps having terminals projecting from the ends thereof, a grinding element engageable with the end of a rst terminal for forming a plateau on the said terminal end, said grinding element having a mounting enabling said element to be shifted in a direction toward said terminal end, a gauge for determining insuiciency of depth of grind of said plateau, an air pressure valve having electric control, an electric circuit from said gauge to said air ,pressure valve, said gauge closing said electric circuit to open said valve when said gauge determines insuiciency of grind of said first terminal, and an air cylinder receiving air pressure from said valve when opened and operative to shift said grinding element to grind the plateau of the next successive terminal deeper.

5. A grinding machine comprising, means for successively advancing lamps in axial parallelism, saidV lamps having terminals projecting from the ends thereof, a grinding element engageable with the end of a rst terminal for forming a plateau on the Ysaid terminal end, a screw for shifting said grinding element in a direction toward said terminal end, pawl and ratchet'means for actuating said screw, air pressure means for actuating said pawl'and ratchet means, an air pressure valve controlling admission of air pressure to said air pressure means, said valve having electric control, a gauge for determining insuiciency of grind of said plateau, an electric circuit from said gauge to said air pressure valve, said gauge closing said electric circuit to open said valve when said gauge determines insufficiency of grind of said first terminal and thereby operating said screw and shifting said grinding element to grind the plateau of the next successive terminal deeper.

6. A grinding machine comprising, means for successively advancing lamps in axial parallelism with an indexing motion and for providing periods of rest between periods of advancement of such lamps, said larnps each having a terminal projecting from an end thereof, a carriage proximate to the end of a lamp terminal at a location of the lamp at a said period of rest, said carriage being Y movable in a direction transverse to the axis of the lamp terminal, and said carriage having a stop for engagement thereagainst of said lamp terminal for locating said terminal longitudinally, said carriage also having a grinding element movable with the carriage to a position of engagement with said lamp terminal end after the carriage moves said stop away from said terminal, and said carriage having a gauge subsequently engageable with said terminal when the carriage moves the grinding element away from said terminal.

References Cited in the file of this patent UNITEDSTATES PATENTS 1,891,662 Booth et al Dec. 20, 1932 2,110,931 Dyer et al Mar. 15, 1938 2,692,457 Bindszus Oct. 26, 1954 

1. A GRINDING MACHINE COMPRISING, MEANS FOR SUCCESSIVELY ADVANCING LAMPS IN AXIAL PARALLELISM WITH LAMP TERMINALS PROJECTING FROM THE ENDS OF SAID LAMPS, A GRINDING ELEMENT ENGAGEABLE WITH THE END OF A TERMINAL OF A FIRST LAMP FOR FORMING A PLATEAU ON THE END OF SAID TERMINAL, AND MEANS GAUGING THE DEPTH OF GRIND OF SAID FORMED PLATEAU FOR DETERMINING DEPTH OF GRIND OF PLATEAU FOR THE NEXT SUCCESSIVE LAMP TERMINAL. 